WO2023132151A1

WO2023132151A1 - Image capturing element and electronic device

Info

Publication number: WO2023132151A1
Application number: PCT/JP2022/043667
Authority: WO
Inventors: 俊久牧平; 秀樹田中
Original assignee: ソニーセミコンダクタソリューションズ株式会社
Priority date: 2022-01-07
Filing date: 2022-11-28
Publication date: 2023-07-13
Also published as: JPWO2023132151A1

Abstract

An image capturing element according to the present invention is provided with: a first pixel block which has a plurality of pixels mutually including color filters of the same first color; and a second pixel block which has a plurality of pixels including color filters of a second color different from that of the first pixel block, and which has a different number of pixels than the number of pixels in the first pixel block. The first pixel block and the second pixel block are configured so as to share, among the plurality of pixels, pixel constituent elements downstream of a load voltage conversion unit. Also included is a signal quantity adjustment unit which adjusts the output signal quantities output by the pixels in the first pixel block and the second pixel block. The signal quantity adjustment unit adjusts output signal quantities such that the output signal quantity of the first color matches the output signal quantity of the second color.

Description

Image sensor and electronic equipment

This technology relates to imaging devices. More specifically, the present invention relates to an image pickup device having a pixel structure that obtains an image plane phase difference, and an electronic device having the image pickup device.

　Electronic devices equipped with imaging functions, typified by digital still cameras, employ an autofocus method that automatically focuses on the subject. One of the autofocus methods is a phase difference method, and one of the phase difference methods is an image plane phase difference method (see, for example, Patent Document 1).

WO2016/098640

The above-described conventional technology discloses an imaging device that includes normal pixels for obtaining pixel signals that form a captured image and phase difference detection pixels for obtaining an image plane phase difference. Since it is desired that the image quality of an image captured by an image sensor is high, it is expected that the pixel size will become finer in the future as the number of pixels increases. In the conventional technology described above, the phase difference detection pixel is composed of two pixels adjacent to each other, and the basic configuration is a pixel structure in which one on-chip lens is formed for the two pixels. Therefore, even if the pixel size is miniaturized with the improvement of the image quality of the captured image, there is an image sensor that can contribute to the realization of high-precision autofocus while maintaining the basic pixel structure of the phase difference detection pixel. desired.

This technology was created in view of this situation, and even if the pixel size is reduced as the quality of the captured image increases, the basic configuration of the phase difference detection pixel is maintained. It is an object of the present invention to contribute to realization of high-precision autofocus.

The present technology has been made to solve the above-described problems, and a first aspect thereof is a first pixel block having a plurality of pixels each including a color filter of a first color that is the same as each other. each of which has a plurality of pixels including a color filter of a second color that is the same as that of the first pixel block and different from that of the first pixel block, and has a number of pixels different from that of the first pixel block. 2 pixel blocks, each of the first pixel block and the second pixel block having a plurality of pixel pairs of two pixels, corresponding to the plurality of pixel pairs. A plurality of lenses are provided at each position, and the first pixel block and the second pixel block have a pixel configuration after the charge-voltage conversion unit that converts the charge obtained by the photoelectric conversion unit into voltage. It has a pixel-sharing configuration in which an element is shared among a plurality of pixels, and further includes a signal amount adjustment unit for adjusting an output signal amount output from each pixel of the first pixel block and the second pixel block. and the signal amount adjustment unit adjusts the output signal amount for the first color output from the first pixel block and the output signal amount for the second color output from the second pixel block. It is an imaging device that adjusts the output signal amount so that the signal amount matches the signal amount. As a result, even if the pixel size is reduced as the image quality of the captured image increases, it is possible to contribute to the realization of high-precision autofocus while maintaining the basic configuration of the phase difference detection pixel. Furthermore, even if the number of pixels in each color pixel block is different, there is an effect that an output signal amount proportional to the exposure time can be obtained. Here, "matching" means not only strictly matching but also substantially matching, and various variations caused by design or manufacturing are allowed.

Further, in the first aspect, the signal amount adjustment unit may adjust the output signal amount for the first color output from the first pixel block and the output signal amount for the first color output from the second pixel block. The output signal amount of the second color is adjusted so that the output signal amount of the color with the smaller signal amount matches the output signal amount of the color with the larger signal amount. can be This brings about the effect of being able to absorb the difference in the output signal amount of each color.

Further, in the first aspect, the signal amount adjusting section is set to a first driving mode for individually reading signals of pixels of the first pixel block and the second pixel block, and a driving mode of the pixel pair. In the second drive mode for adding and reading out the signals of the two pixels, the output signal amount for the first color output from the first pixel block is The output signal amount may be adjusted so as to match the output signal amount for the output second color. This brings about the effect of being able to absorb the difference in the output signal amount of each color in the first drive mode and the second drive mode.

Further, in the first aspect, in the third drive mode for adding and reading out the signals of all the pixels in the first pixel block and the second pixel block, the signal amount adjusting section may of the output signal amount so as to match the output signal amount of the first color output from the first pixel block with the output signal amount of the second color output from the pixel block of Adjustments may be made. As a result, in the third drive mode, it is possible to absorb the difference in the output signal amount of each color.

In the first aspect, the signal amount adjustment unit adjusts the output signal amount by converting the analog signal output from each pixel of the first pixel block and the second pixel block into a digital signal. It may be performed by digital gain adjustment in the digital domain after conversion. This brings about the effect that the process of absorbing the difference in the output signal amount of each color can be performed in the digital domain.

Further, in the first aspect, the signal amount adjustment unit adjusts the output signal amount for each color by converting the analog signal output from each pixel of the first pixel block and the second pixel block into a digital signal. It may be done by analog gain adjustment in the analog domain before conversion to signal. This brings about the effect that the process of absorbing the difference in the output signal amount of each color can be performed in the analog domain.

Further, in the first aspect, the analog-to-digital converter that converts an analog signal to a digital signal converts a reference signal of a ramp wave whose level changes with a predetermined slope over time during analog-to-digital conversion. A single-slope type analog-to-digital conversion unit used as a reference signal for the signal amount adjustment unit may perform analog gain adjustment by changing the slope of the reference signal of the ramp wave. As a result, by changing the slope of the reference signal of the ramp wave, it is possible to absorb the difference in the output signal amount of each color.

Further, on the first side surface, the two pixels are arranged side by side in the first direction, and in each of the first pixel block and the second pixel block, a second pixel block intersects the first direction. The two pixel pairs lined up in the direction may be shifted in the first direction. This brings about an effect that the pixels can be arranged densely in the pixel array section.

In addition, a second aspect of the present technology includes: a first pixel block having a plurality of pixels each including a color filter of a first color that is the same as each other; a second pixel block having a plurality of pixels including a color filter of a second color different from that of the pixel block and having a number of pixels different from that of the first pixel block; and an analog-to-digital converter for converting an analog signal output from each pixel of two pixel blocks into a digital signal, wherein the first pixel block and the second pixel block each include two pixels. and a plurality of lenses are provided at respective positions corresponding to the plurality of pixel pairs, and the first pixel block and the second pixel block are photoelectric It has a pixel-sharing configuration in which the pixel-constituting elements after the charge-voltage conversion unit that converts the charge obtained by the conversion unit into voltage are shared among a plurality of pixels. A single-slope analog-to-digital conversion unit that uses a ramp wave reference signal given from as a reference signal in analog-to-digital conversion, and the reference signal generation unit is a ramp wave reference signal with a different slope. is provided with a plurality of reference signal generation units that generate the and further includes a signal amount adjustment unit that adjusts the output signal amount output from each pixel of the first pixel block and the second pixel block, The signal amount adjustment unit adjusts the first color output from the first pixel block based on the ramp wave reference signals with different slopes generated by the plurality of reference signal generation units. The imaging device adjusts the output signal amount so that the output signal amount and the output signal amount for the second color output from the second pixel block match. As a result, even if the pixel size is reduced as the image quality of the captured image increases, it is possible to contribute to the realization of high-precision autofocus while maintaining the basic configuration of the phase difference detection pixel. Furthermore, even if the number of pixels in each color pixel block is different, there is an effect that an output signal amount proportional to the exposure time can be obtained.

In the second aspect, among the plurality of reference signal generators, a reference signal generator for adjusting an output signal amount for the first color output from the first pixel block; It may be a reference signal generator for adjusting the output signal amount for the second color output from the second pixel block. As a result, the process of absorbing the difference in the output signal amount of each color output from each pixel block can be performed by adjusting the inclination of the reference signal of the ramp wave generated by the two reference signal generation units. bring about action.

In addition, a third aspect of the present technology includes: a first pixel block having a plurality of pixels each including a color filter of a first color that is the same as each other; a second pixel block having a plurality of pixels including a color filter of a second color different from the pixel block and having a number of pixels different from that of the first pixel block; and the second pixel blocks each have a plurality of pixel pairs each having two pixels, and a plurality of lenses are provided at respective positions corresponding to the plurality of pixel pairs, and the The first pixel block and the second pixel block have a pixel-sharing configuration in which a plurality of pixels share the pixel constituent elements after the charge-voltage conversion unit that converts the charge obtained by the photoelectric conversion unit into voltage. and further comprising a signal amount adjustment section for adjusting an output signal amount output from each pixel of the first pixel block and the second pixel block, wherein the signal amount adjustment section adjusts the output signal amount of the first pixel block. The output signal amount is adjusted so that the output signal amount for the first color output from the block and the output signal amount for the second color output from the second pixel block match. An electronic device having an image sensor. This contributes to the realization of high-precision autofocus while maintaining the basic configuration of the phase-difference detection pixels, even if the pixel size of the image sensor is reduced as the quality of the captured image increases. Furthermore, even if the number of pixels in each color pixel block is different, it is possible to obtain an output signal amount proportional to the exposure time.

It is a block diagram showing an example of 1 composition of an image sensor in a 1st embodiment of this art. FIG. 2 is a plan view showing an example of pixel arrangement in a pixel array section of the image pickup device according to the first embodiment; FIG. 2 is a cross-sectional view showing an example of a schematic cross-sectional structure of a pixel array portion of the image pickup device according to the first embodiment; 3 is a circuit diagram showing an example of a circuit configuration of a green (Gr) pixel block shown in FIG. 2; FIG. 3 is a circuit diagram showing an example of a circuit configuration of a red (R) pixel block shown in FIG. 2; FIG. 3 is a block diagram showing an example of the configuration of a readout section of the image sensor in the first embodiment; FIG. FIG. 2 is a diagram showing an example of the structure of an image signal Spic output from an imaging element in the first embodiment; FIG. 1 is a perspective view schematically showing a flat-type semiconductor chip structure and a stacked-type semiconductor chip structure; FIG. 4 is a block diagram showing one configuration example of a signal amount adjustment unit of the image sensor in the first embodiment; FIG. FIG. 10 is a diagram illustrating adjustment of the output signal amount in the case of all-pixel readout mode and AF mode; FIG. 10 is a diagram illustrating adjustment of the output signal amount in the case of all-pixel addition mode; It is a circuit diagram showing a configuration example of an analog-digital conversion unit according to a second embodiment of the present technology. FIG. 3 is a waveform diagram showing timing relationships among a waveform of a reference signal RAMP at high gain, a waveform of a reference signal RAMP at low gain, a waveform of a signal line VSL, and clocks of a counter; 1 is a block diagram showing a configuration example of an imaging device, which is an example of electronic equipment to which the present technology is applied; FIG. It is a figure showing an example of a field to which an embodiment of this art is applied. 1 is a block diagram showing a schematic configuration example of a vehicle control system; FIG. FIG. 4 is an explanatory diagram showing an example of an installation position of an imaging unit;

Hereinafter, a form for carrying out the present technology (hereinafter referred to as an embodiment) will be described. Explanation will be given in the following order.
1. First Embodiment (Control for Absorbing Differences in Output Signal Amounts by Color: Example Performed by Digital Gain Correction Processing)
2. Second Embodiment (Control for Absorbing Differences in Output Signal Amounts by Color: Example of Analog Gain Correction Processing)
3. Modification 4. Application example to electronic equipment 5 . Application example of the embodiment of the present technology6. Example of application to a moving object 7. Possible configurations for this technology

<1. First Embodiment>
As an imaging element of the present technology, for example, a CMOS (Complementary Metal Oxide Semiconductor) image sensor, which is a type of XY addressing imaging element, can be exemplified. A CMOS image sensor is an imaging device manufactured by applying or partially using a CMOS process.

[One configuration example of the imaging element]
FIG. 1 is a block diagram showing a configuration example of an imaging device according to a first embodiment of the present technology. The imaging device 1 includes a pixel array section 11, a driving section 12, a reading section 13, a reference signal generating section 14, a signal processing section 15, a storage section (data storage section) 16, and an imaging control section 17. It's becoming

The pixel array section 11 has a configuration in which pixels (pixel circuits) 20 including photoelectric conversion sections (photoelectric conversion elements) are two-dimensionally arranged in row and column directions, that is, in a matrix. Here, the row direction refers to the arrangement direction of the pixels 20 in the pixel row, and the column direction refers to the arrangement direction of the pixels 20 in the pixel column. The pixels 20 perform photoelectric conversion to generate and store photocharges corresponding to the amount of received light. The pixel 20 generates a signal SIG containing a pixel voltage Vpix corresponding to the amount of incident light received.

The drive unit 12 is composed of a shift register, an address decoder, and the like, and when selecting each pixel 20 of the pixel array unit 11, based on a timing control signal supplied from the imaging control unit 17, scans the pixel rows and performs pixel row selection. Drive to control the address. A signal SIG including the pixel voltage Vpix is output from each pixel 20 of the pixel array section 11 under the driving by the driving section 12 .

The reading unit 13 includes, for example, a single-slope type analog-digital conversion unit, which will be described later. , the signal SIG including the pixel voltage Vpix is subjected to analog-to-digital conversion (AD conversion). The reading unit 13 outputs the analog-digital converted signal as the image signal Spic0.

The reference signal generation unit 14 generates a reference signal RAMP that is used as a reference signal for analog-to-digital conversion in the single-slope analog-to-digital conversion unit of the reading unit 13 . The reference signal RAMP is a so-called ramp wave signal whose level (voltage) changes (for example, monotonously decreases) with a predetermined slope over time.

Under the control of the imaging control unit 17, the signal processing unit 15 performs predetermined signal processing on the image signal Spic0 supplied from the reading unit 13, and outputs it as an image signal Spic. The signal processing section 15 is configured to have an image data generation section 151 and a phase difference data generation section 152 .

In the signal processing unit 15, the image data generation unit 151 is configured to generate image data DP representing a captured image by performing predetermined image processing based on the image signal Spic0. The phase difference data generator 152 is configured to generate phase difference data DF indicating the image plane phase difference by performing predetermined image processing based on the image signal Spic0.

The signal processing unit 15 outputs an image signal Spic including the image data DP generated by the image data generation unit 151 and the phase difference data DF generated by the phase difference data generation unit 152 .

For example, when the signal processing unit 15 performs signal processing, the storage unit (data storage unit) 16 temporarily stores (stores) data necessary for the processing.

The imaging control unit 17 generates various timing signals, clock signals, control signals, etc. based on an externally applied control signal Sctl, and based on these generated signals, the driving unit 12, reading unit 13, The operation of the image sensor 1 is controlled by controlling the driving of the reference signal generation unit 14, the signal processing unit 15, and the like. The imaging control unit 17 controls the imaging operation of the imaging element 1 based on the control signal Sctl.

[Example of pixel arrangement]
FIG. 2 is a plan view showing an example of arrangement of the pixels 20 in the pixel array section 11. As shown in FIG. As shown in FIG. 2 , the pixel array section 11 has a plurality of pixel blocks 100 and a plurality of lenses 101 .

The plurality of pixel blocks 100 includes pixel block 100R, pixel block 100Gr, pixel block 100Gb, and pixel block 100B. In the pixel array section 11, the plurality of pixels 20 are arranged in units (units U) of four pixel blocks 100 (pixel blocks 100R, 100Gr, 100Gb, and 100B).

The pixel block 100R has eight pixels 20R including a red (R) color filter 115 (see FIG. 3). A pixel block 100Gr has ten pixels 20Gr including a green (G) color filter 115 . A pixel block 100Gb has ten pixels 20Gb including a green (G) color filter 115 . Pixel block 100B has eight pixels 20B including blue (B) color filter 115 . In FIG. 2, the difference in color of the color filters is expressed using hatching.

The arrangement pattern of the eight pixels 20R in the pixel block 100R and the arrangement pattern of the eight pixels 20B in the pixel block 100B are the same. The arrangement pattern of the ten pixels 20Gr in the pixel block 100Gr and the arrangement pattern of the ten pixels 20Gb in the pixel block 100Gb are the same. In the unit U, the pixel block 100Gr is located at the upper left, the pixel block 100R is located at the upper right, the pixel block 100B is located at the lower left, and the pixel block 100Gb is located at the lower right.

The arrangement of the pixel block 100R, the pixel block 100Gr, the pixel block 100Gb, and the pixel block 100B is a so-called RGB Bayer arrangement. That is, the pixel block 100R, the pixel block 100Gr, the pixel block 100Gb, and the pixel block 100B are arrayed in the RGB Bayer array with the pixel block 100 as a unit.

Red (R) and blue (B) are examples of the first color described in the claims, and green (Gr, Gb) are examples of the second color described in the claims. is. The pixel block 100R and the pixel block 100B are examples of the first pixel block described in the claims, and the pixel block 100Gr and the pixel block 100Gb are examples of the second pixel block described in the claims. An example.

[Example of cross-sectional structure of pixel array part]
FIG. 3 is a cross-sectional view showing an example of a schematic cross-sectional structure of the pixel array section 11. As shown in FIG. As shown in FIG. 3, the pixel array section 11 includes a plurality of lenses 101, a semiconductor substrate 111, a semiconductor region 112, an insulating layer 113, a multilayer wiring layer 114, a color filter 115, and a light shielding film 116. .

The semiconductor substrate 111 is a support substrate on which the imaging element 1 is formed, and is, for example, a P-type semiconductor substrate. The semiconductor region 112 is a semiconductor region provided at a position corresponding to each of the plurality of pixels 20 in the semiconductor substrate 111, and is doped with an N-type impurity to form a photoelectric conversion portion (for example, a photodiode). ) is formed. The insulating layer 113 is provided in the substrate of the semiconductor substrate 111 at the boundary of the plurality of pixels 20 arranged in parallel on the XY plane. be.

The multilayer wiring layer 114 is provided on the semiconductor substrate 111 on the side opposite to the light incident side (lens 101 side) of the pixel array section 11, and includes a plurality of wiring layers and interlayer insulating films. The wiring in the multilayer wiring layer 114 is configured to connect, for example, a transistor (not shown) provided on the surface of the semiconductor substrate 111 to the driving section 12 and the reading section 13 .

The color filter 115 is provided on the semiconductor substrate 111 on the light incident side of the pixel array section 11 . Here, in the XY plane, when the first direction is the X direction and the second direction is the Y direction, the light shielding films 116 are arranged side by side in the X direction on the light incident side of the pixel array section 11 . It is provided so as to surround one pixel 20 . The two pixels 20 arranged side by side in the X direction are hereinafter also referred to as a pixel pair 90 .

The multiple lenses 101 are so-called on-chip lenses, and are provided on the color filter 115 on the light incident side of the pixel array section 11 . A plurality of lenses 101 are provided above two pixels 20 (pixel pairs 90) arranged side by side in the X direction. Four lenses 101 are provided above the eight pixels 20 of the pixel block 100R. Five lenses 101 are provided above the ten pixels 20 of the pixel block 100Gr. Five lenses 101 are provided above the ten pixels 20 of the pixel block 100Gb. Four lenses 101 are provided above the eight pixels 20 of the pixel block 100B.

A plurality of lenses 101 are arranged side by side in the X direction and the Y direction. The lenses 101 arranged in the Y direction are arranged with a shift of one pixel 20 in the X direction. In other words, the pixel pairs 90 aligned in the Y direction are shifted by one pixel 20 in the X direction.

With this configuration, the images of the two pixels 20 of the pixel pair 90 corresponding to one lens 101 are shifted from each other. The imaging device 1 generates phase difference data DF based on so-called image plane phase differences detected by the plurality of pixel pairs 90 . That is, the two pixels 20 of the pixel pair 90 corresponding to one lens 101 are phase difference detection pixels for generating the phase difference data DF based on the image plane phase difference. 2. Description of the Related Art An electronic device having an imaging function such as a digital still camera determines the defocus amount based on the phase difference data DF, and moves the position of the photographing lens based on the defocus amount. In this manner, autofocus can be realized in an electronic device having an imaging function.

[Example of circuit configuration of pixel block]
Next, as an example of the circuit configuration of the pixel block 100, a green (Gr) pixel block 100Gr having ten pixels 20Gr and a red (R) pixel block 100R having eight pixels 20R are taken as examples. explain. FIG. 4 is a circuit diagram showing an example of the circuit configuration of the green (Gr) pixel block 100Gr. FIG. 5 is a circuit diagram showing an example of the circuit configuration of the red (R) pixel block 100R.

The pixel array section 11 has a plurality of control lines TRGL, a plurality of control lines RSTL, a plurality of control lines SELL, and a plurality of signal lines VSL.

The control line TRGL is wired along the row direction for each pixel row of the pixel array section 11 , and one end is connected to the corresponding output terminal of the driving section 12 . A control signal is appropriately supplied from the drive unit 12 to the control line TRGL. The control line RSTL is wired along the row direction for each pixel row of the pixel array section 11 , and one end is connected to the corresponding output terminal of the driving section 12 . A control signal is appropriately supplied from the drive unit 12 to the control line RSTL.

The control line SELL is wired along the row direction for each pixel row of the pixel array section 11 , and one end is connected to the corresponding output terminal of the drive section 12 . A control signal is appropriately supplied from the drive unit 12 to the control line SELL. The signal line VSL is wired along the column direction for each pixel column of the pixel array section 11 , and one end is connected to the readout section 13 . This signal line VSL transmits the signal SIG output from the pixel 20 to the reading unit 13 .

A green (Gr) pixel block 100Gr shown in FIG. 4 has ten photoelectric conversion units 21 and ten transfer transistors 22 . The pixel block 100Gr further has one charge-voltage converter 23, one reset transistor 24, one amplifier transistor 25, and one selection transistor 26. FIG.

Here, as the transfer transistor 22, the reset transistor 24, the amplification transistor 25, and the selection transistor 26, for example, an N-type MOS (Metal Oxide Semiconductor) field effect transistor can be used. However, the combination of the conductivity types of the transfer transistor 22, the reset transistor 24, the amplification transistor 25, and the selection transistor 26 illustrated here is merely an example, and the combination is not limited to these combinations.

The 10 photoelectric conversion units 21 and the 10 transfer transistors 22 respectively correspond to the 10 pixels 20Gr included in the pixel block 100Gr. The pixel block 100Gr has a configuration of a so-called pixel shared pixel circuit in which the charge-voltage converter 23, the reset transistor 24, the amplification transistor 25, and the selection transistor 26 are shared among the ten pixels 20Gr. there is

The photoelectric conversion unit 21 is a PN junction photodiode (PD: Photo Diode). The photodiode has an anode electrode connected to a low-potential power supply (for example, ground), generates an amount of charge corresponding to the amount of light received, and accumulates the generated charge inside. A cathode electrode of the photodiode 21 is connected to a source electrode of the transfer transistor 22 .

The transfer transistor 22 has a gate electrode connected to the control line TRGL, a source electrode connected to the cathode electrode of the photoelectric conversion unit 21 , and a drain electrode connected to the charge-voltage conversion unit 23 . Gate electrodes of ten transfer transistors 22 are connected to different control lines TRGL among ten control lines TRGL (control lines TRGL1 to TRGL6 and TRGL9 to TRGL12 in this example).

The charge-voltage converter 23 is a capacitance _CFD of a floating diffusion (FD) region formed between the drain region of the transfer transistor 22 and the source region of the reset transistor 24 . The charge-voltage conversion unit 23 converts the charge photoelectrically converted by the photoelectric conversion unit 21 and transferred from the photoelectric conversion unit 21 by the transfer transistor 22 into a voltage.

The reset transistor 24 has a gate electrode connected to the control line RSTL and a source electrode connected to the charge-voltage converter 23 . A power supply voltage V _DD is supplied to the drain electrode of the reset transistor 24 . The reset transistor 24 resets the charge accumulated in the charge-voltage conversion section 23 according to a control signal given from the drive section 12 through the control line RSTL.

The amplification transistor 25 has a gate electrode connected to the charge-voltage converter 23 and a source electrode connected to the drain electrode of the selection transistor 26 . A power supply voltage V _DD is supplied to the drain electrode of the amplification transistor 25 . The amplification transistor 25 serves as an input section of a circuit for reading out charges obtained by photoelectric conversion in the photoelectric conversion section 21, that is, a source follower circuit. That is, the amplification transistor 25 is connected to one end of the signal line VSL by connecting the source electrode to the signal line VSL through the selection transistor 26, and the constant current source I (see FIG. 6) and the source are connected to one end of the signal line VSL. Construct a follower circuit.

The selection transistor 26 has a gate electrode connected to the control line SELL, a drain electrode connected to the source electrode of the amplification transistor 25, and a source electrode connected to the signal line VSL. Then, the selection transistor 26 selects one of the pixels 20 in the pixel array section 11 under selective scanning by the driving section 12 .

In the circuit configuration described above, in the pixel 20, the transfer transistor 22 and the reset transistor 24 are turned on, thereby discharging the charge accumulated in the photoelectric conversion section 21. Then, when the transfer transistor 22 and the reset transistor 24 are turned off, an exposure period is started, photoelectric conversion is performed in the photoelectric conversion section 21, and an amount of charge corresponding to the amount of received light is accumulated.

After the exposure period ends, the pixel 20 outputs the signal SIG including the reset voltage Vreset and the pixel voltage Vpix to the signal line VSL. Specifically, first, the pixel 20 is electrically connected to the signal line VSL by turning on the selection transistor 26 . Thereby, the amplification transistor 25 is electrically connected to a constant current source I (see FIG. 6), which will be described later, connected to one end of the signal line VSL at the input portion of the readout portion 13, and operates as a source follower.

Then, as will be described later, the pixel 20 is in the P phase (Pre-charge phase) period after the voltage of the charge-voltage converter 23 is reset by turning on the reset transistor 24, and the charge at that time is The voltage of the voltage converter 23 is output as the reset voltage Vreset. In addition, the transfer transistor 22 is turned on, so that the pixel 20 performs the charge-voltage conversion during the D phase (data phase) period after the charge is transferred from the photoelectric conversion unit 21 to the charge-voltage conversion unit 23 . The voltage of the section 23 is output as the pixel voltage Vpix. A difference voltage between the pixel voltage Vpix and the reset voltage Vreset corresponds to the amount of light received by the pixel 20 during the exposure period. Thus, the pixel 20 outputs the signal SIG including the reset voltage Vreset and pixel voltage Vpix to the signal line VSL.

A red (R) pixel block 100 R shown in FIG. 5 has eight photoelectric conversion units 21 and eight transfer transistors 22 . The pixel block 100R further has one charge-voltage converter 23, one reset transistor 24, one amplifier transistor 25, and one selection transistor 26. FIG.

Here, as the transfer transistor 22, the reset transistor 24, the amplification transistor 25, and the selection transistor 26, for example, an N-type MOS field effect transistor can be used. However, the combination of the conductivity types of the transfer transistor 22, the reset transistor 24, the amplification transistor 25, and the selection transistor 26 illustrated here is merely an example, and the combination is not limited to these combinations.

The eight photoelectric conversion units 21 and the eight transfer transistors 22 respectively correspond to the eight pixels 20R included in the pixel block 100R. The pixel block 100R has a pixel circuit configuration in which the charge-voltage converter 23, the reset transistor 24, the amplification transistor 25, and the selection transistor 26 are shared among the ten pixels 20R. The gate electrodes of the eight transfer transistors 22 are connected to different control lines TRGL among the eight control lines TRGL (control lines TRGL1, TRGL2, TRGL5 to TRGL10 in this example).

Although not shown, the pixel block 100Gb has 10 photoelectric conversion units 21 and 10 transfer transistors 22, like the pixel block 100Gr shown in FIG. Ten photoelectric conversion units 21 and ten transfer transistors 22 respectively correspond to ten pixels 20Gb included in the pixel block 100Gb. A gate electrode of the transfer transistor 22 is connected to different control lines TRGL among the ten control lines TRGL.

The pixel block 100Gb further has one charge-voltage converter 23, one reset transistor 24, one amplifier transistor 25, and one selection transistor 26. The pixel block 100Gb has a pixel circuit configuration in which the charge-voltage converter 23, the reset transistor 24, the amplification transistor 25, and the selection transistor 26 are shared among the ten pixels 20Gb.

Also, the pixel block 100B has eight photoelectric conversion units 21 and eight transfer transistors 22, like the pixel block 100R shown in FIG. The eight photoelectric conversion units 21 and the eight transfer transistors 22 respectively correspond to the eight pixels 20B included in the pixel block 100B. A gate electrode of the transfer transistor 22 is connected to different control lines TRGL among the eight control lines TRGL.

The pixel block 100B further has one charge-voltage converter 23, one reset transistor 24, one amplifier transistor 25, and one selection transistor 26. The pixel block 100B has a pixel circuit configuration in which the charge-voltage converter 23, the reset transistor 24, the amplification transistor 25, and the selection transistor 26 are shared among the eight pixels 20B.

[Configuration example of reading unit]
Next, a configuration example of the reading unit 13 will be described. FIG. 6 is a block diagram showing an example of the configuration of the reading section 13 of the imaging device 1 according to the first embodiment. In addition to the reading unit 13, FIG. 6 also shows the reference signal generating unit 14, the signal processing unit 15, and the imaging control unit 17.

A signal SIG including a pixel voltage Vpix read from each pixel 20 of the pixel array section 11 via a plurality of signal lines VSL is input to the reading section 13 . A constant current source I is connected to each of the plurality of signal lines VSL in the input section of the reading section 13 . The constant current source I has one end connected to the corresponding signal line VSL and the other end grounded, and acts to supply a predetermined current to the corresponding signal line VSL.

The reading unit 13 has a plurality of analog-digital conversion units 31 and transfer control units 32 . A plurality of analog-to-digital converters 31 are provided corresponding to the plurality of signal lines VSL, respectively, and perform analog-to-digital conversion on the signal SIG on the corresponding signal line VSL. The analog-digital converter 31 corresponding to one signal line VSL will be described below.

The analog-digital conversion section 31 is configured to have

capacitive elements

311 and 312, a comparison circuit 313, a counter 314, and a latch circuit 315.

The capacitive element 311 has one end connected to the signal line VSL and the other end connected to one input end of the comparison circuit 313 . A signal SIG including the pixel voltage Vpix is supplied from each pixel 20 of the pixel array section 11 to the capacitive element 311 through the signal line VSL.

The capacitive element 312 has one end connected to the signal line 33 that transmits the reference signal RAMP, and the other end connected to the other input end of the comparison circuit 313 . A reference signal RAMP is supplied from the reference signal generator 14 to the capacitive element 312 through the signal line 33 .

The comparison circuit 313 is supplied with a signal SIG supplied from each pixel 20 of the pixel array section 11 via the signal line VSL and the capacitive element 311, and supplied from the reference signal generation section 13 via the signal line 33 and the capacitive element 312. It compares with the reference signal RAMP and outputs the signal Vcp as a result of the comparison.

The comparison circuit 313 sets the operating point by setting the voltages of the

capacitive elements

311 and 312 based on the control signal AZ supplied from the imaging control section 17 through the signal line 34 . After setting the operating point, the comparison circuit 313 performs a comparison operation of comparing the reset voltage Vreset included in the signal SIG and the voltage of the reference signal RAMP in the P-phase period. Also, the comparison circuit 313 performs a comparison operation of comparing the pixel voltage Vpix included in the signal SIG with the voltage of the reference signal RAMP during the D-phase period.

The counter 314 is configured to count pulses of the clock signal CLK supplied from the imaging control unit 17 based on the signal Vcp supplied from the comparison circuit 313 . Specifically, the counter 314 generates the count value CNTP by counting the pulses of the clock signal CLK until the signal Vcp output from the comparison circuit 313 transitions during the P-phase period. Output as a digital code with multiple bits. Further, the counter 314 generates a count value CNTD by counting the pulses of the clock signal CLK until the signal Vcp output from the comparison circuit 313 transitions during the D-phase period, and converts the count value CNTD into a plurality of bits. output as a digital code having

The latch circuit 315 temporarily holds the digital code supplied from the counter 314 and outputs the digital code to the bus wiring 35 based on the instruction from the transfer control section 32 .

The transfer control unit 32 controls the latch circuits 315 of the plurality of analog-digital conversion units 31 to sequentially output the digital code to the bus wiring 35 based on the control signal CTL supplied from the imaging control unit 17 . The reading unit 13 uses the bus wiring 35 to sequentially transfer the plurality of digital codes output from the plurality of analog-digital conversion units 31 to the signal processing unit 15 as the image signal Spic0.

Under the control of the imaging control unit 17, the signal processing unit 15 performs predetermined signal processing on the image signal Spic0 supplied from the reading unit 13 to generate an image signal including the image data DP and the phase difference data DF. Output as Spic. Specifically, as shown in FIG. 7, the signal processing unit 15 generates and outputs the image signal Spic by alternately arranging the phase difference data DF related to the pixels 20 in a plurality of rows.

[Semiconductor chip structure]
Examples of the semiconductor chip structure of the imaging device 1 having the above-described configuration include a so-called parallel-type semiconductor chip structure and a so-called stacked-type semiconductor chip structure. In addition, regarding the pixel structure, when the substrate surface on which the wiring layer is formed is defined as the front surface (front surface), it is also possible to adopt a back-illuminated pixel structure in which light emitted from the back surface on the opposite side is taken in. Alternatively, a surface-illuminated pixel structure that captures light emitted from the surface side may be employed.

The outline of the parallel-type semiconductor chip structure and the stacked-type semiconductor chip structure will be described below.

(Horizontal type semiconductor chip structure)
A in FIG. 8 is a perspective view schematically showing a flat-type chip structure of the imaging device 1 . In the parallel-type semiconductor chip structure, each component of the peripheral circuit section of the pixel array section 11 is formed on the same semiconductor substrate (semiconductor chip) 41 as the pixel array section 11 in which the pixels 20 are arranged in a matrix. It has become. Specifically, on the same semiconductor substrate 41 as the pixel array section 11, the driving section 12, the reading section 13, the reference signal generating section 14, the signal processing section 15, the imaging control section 17, and the like are formed. Pads 42 for external connection and power supply are provided, for example, at both left and right ends of the semiconductor substrate 41 .

(Stacked semiconductor chip structure)
b in FIG. 8 is an exploded perspective view schematically showing the laminated semiconductor chip structure of the imaging device 1 . The laminated semiconductor chip structure has a structure in which at least two semiconductor substrates, ie, a first-layer semiconductor substrate 43 and a second-layer semiconductor substrate 44 are laminated.

In this stacked semiconductor chip structure, the semiconductor substrate 43 of the first layer is a pixel chip in which the pixel array section 11 in which the pixels 20 are two-dimensionally arranged in a matrix is formed. Pads 42 for external connection and power supply are provided, for example, at both left and right ends of the semiconductor substrate 43 of the first layer.

The semiconductor substrate 44 of the second layer is formed with the peripheral circuit portion of the pixel array portion 11, that is, the driving portion 12, the reading portion 13, the reference signal generating portion 14, the signal processing portion 15, the imaging control portion 17, and the like. A circuit chip. Note that the arrangement of the driving section 12, the reading section 13, the reference signal generating section 14, the signal processing section 15, the imaging control section 17, etc. is an example, and is not limited to this arrangement example.

The pixel array portion 11 on the semiconductor substrate 43 of the first layer and the peripheral circuit portion on the semiconductor substrate 44 of the second layer are metal-metal junctions including Cu--Cu junctions, Through Silicon Via (TSV) ), and are electrically connected via

bonding portions

45 and 46 composed of microbumps or the like.

According to the stacked semiconductor chip structure described above, a process suitable for manufacturing the pixel array section 11 can be applied to the semiconductor substrate 43 of the first layer, and a process suitable for manufacturing the circuit portion can be applied to the semiconductor substrate 44 of the second layer. process can be applied. As a result, the process can be optimized in manufacturing the imaging device 1 . In particular, when fabricating the circuit portion, there is an advantage that it is possible to apply advanced processes and to expand the scale of the circuit.

[About pixel blocks and pixel pairs]
As described above, the image sensor 1 according to the first embodiment includes a plurality of pixel blocks 100 each having a plurality of pixels 20 including color filters of the same color. A plurality of pixels 20 in pixel block 100 are partitioned into a plurality of pixel pairs 90 each including two pixels 20 . A plurality of lenses 101 are provided at positions corresponding to the plurality of pixel pairs 90 .

With the configuration described above, the imaging element 1 according to the first embodiment can generate the phase difference data DF with high resolution over the entire surface of the pixel array section 11 . Therefore, in an electronic device having an imaging function such as a digital still camera equipped with such an imaging device 1, highly accurate autofocus can be realized. As a result, the imaging device 1 can improve the image quality, so that a more legible captured image can be obtained.

Also, in the image sensor 1, the number of pixels in a certain pixel block 100 is set to be larger than the number of pixels in another certain pixel block 100. Specifically, in the example of the first embodiment, the number of pixels 20Gr in the pixel block 100Gr, the number of pixels 20Gb in the pixel block 100Gb, the number of pixels 20R in the pixel block 100R, and the number of pixels 20G in the pixel block 100B is set larger than the number of pixels 20B in . As a result, for example, it is possible to increase the light receiving sensitivity of green, which has a large number of pixels, so that the image quality of the captured image can be improved, and a more legible captured image can be obtained.

Further, according to the image sensor 1 in the first embodiment, even if the pixel size is reduced as the quality of the captured image is improved, the two phase difference detection pixels, that is, the pixel pairs 90 While maintaining the basic configuration of the pixel 20, it is possible to contribute to the realization of high-precision autofocus in an electronic device having an imaging function such as a digital still camera.

[About the drive mode of the image sensor]
The image pickup device 1 according to the first embodiment is a pixel circuit in which a plurality of pixels 20 share the pixel constituent elements after the charge-voltage converter 23, that is, the reset transistor 24, the amplification transistor 25, and the selection transistor 26. (see FIGS. 4 and 5). The image sensor 1 having the pixel-sharing pixel circuit has a configuration in which three drive modes, for example, a first drive mode, a second drive mode, and a third drive mode, can be set as drive modes. ing.

The first mode is an all-pixel readout mode in which a plurality of pixels 20 sharing pixel constituent elements after the charge-voltage converter 23 are read out individually without addition (pixel addition). The second drive mode is an AF (autofocus) mode in which addition is performed between two pixels 20 forming a pair of pixel pairs 90 to generate phase difference data DF. A third drive mode is an all-pixel addition mode in which addition (pixel addition) is performed among all pixels 20 that share the pixel constituent elements after the charge-voltage converter 23 and readout is performed.

[Regarding the difference in output signal level for each color]
By the way, in the imaging device 1 having a pixel circuit configured to share the pixel constituent elements after the charge-voltage converter 23, if the number of pixels to be shared is different as in the cases of FIGS. 4 and 5, the charge-voltage converter 23 The number of transfer transistors 22 electrically connected to . As a result, since the conversion efficiency of the charge-voltage converter 23 and the amount of charge handled in the all-pixel addition mode differ for each charge-voltage converter 23, the color after analog-to-digital conversion by the analog-to-digital converter 31 is different. A difference occurs in another output signal amount, and an output signal amount proportional to the exposure time cannot be obtained.

The conversion efficiency η of the charge-voltage converter 23 is given by η=1/C. Here, C is the capacitance of the charge-voltage converter 23 including the capacitance _CFD of the floating diffusion region (FD region). In the case of the green (Gr, Gb) pixel blocks 100Gr and 100Gb, the number of pixels sharing the pixel constituent elements after the charge-voltage converter 23 is larger than the red (R) pixel block 100R and the blue (B) pixel block 100R. Therefore, the number of transfer transistors 22 electrically connected to the charge-voltage converter 23 is increased.

As the number of transfer transistors 22 electrically connected to the charge-voltage converter 23 increases, the capacitance C of the charge-voltage converter 23 increases. is smaller than the conversion efficiency of the pixel block 100R/B having a relatively small number of pixels. In addition, since the pixel block 100Gr/Gb and the pixel block 100R/B have different wiring layouts (routing), a corresponding difference in conversion efficiency occurs. Furthermore, in drive modes in which the number of pixels to be added differs, the number of electrons handled by the charge-voltage converter 23 differs for each color.

[About digital gain correction]
In the image sensor 1 according to the first embodiment, in each of the drive modes of the all-pixel readout mode, the AF mode, and the all-pixel addition mode, for the purpose of obtaining an output signal amount proportional to the exposure time, Control is performed to absorb the difference in output signal amount. More specifically, in the first embodiment, in the digital domain after the analog-to-digital conversion by the analog-to-digital converter 31, control to absorb the difference in the output signal amount for each color is performed by digital gain correction processing. to do. A specific example of the digital gain correction process for absorbing the difference in output signal amount for each color will be described below.

　In order to perform correction processing for absorbing the difference in the output signal amount for each color, that is, digital gain correction processing, it is necessary to acquire the output signal amount for each color. Acquisition of the output signal amount for each color is performed using an external measuring device (not shown) in the adjustment stage before shipment of the imaging device 1 . Specifically, the output signal amount for each color is obtained from the pixel addition number for each drive mode and the conversion efficiency used by the charge-voltage converter 23 . The information of the output signal amount for each color obtained in advance in this manner is stored in the storage unit 16 shown in FIG. 1 and shipped.

Here, the difference in output signal amount for each color will be explained. As described above, the conversion efficiency of the pixel block 100Gr/Gb with a relatively large number of pixels is lower than the conversion efficiency of the pixel block 100R/B with a relatively small number of pixels. Therefore, in the case of the all-pixel readout mode in which pixels are read out individually without performing pixel addition, and the AF mode in which two pixels 20 forming a pair of pixels 90 are added together, as shown in a in FIG. The R and B output signal amounts are greater than the G (Gr, Gb) output signal amount, and a difference in output signal amount occurs between the two.

On the other hand, in the case of the all-pixel addition mode in which addition is performed between all pixels 20, the pixel block 100Gr/Gb having a relatively large number of pixels to be added has the number of electrons handled by the charge-voltage converter 23 by all-pixel addition. will increase. Therefore, as shown by a in FIG. 11, the output signal amount of G (Gr, Gb) is larger than the output signal amount of R and B, and a difference in output signal amount is generated between them.

FIG. 9 is a block diagram showing a configuration example of the signal amount adjustment section 50 of the imaging device 1 according to the first embodiment. In addition to the signal amount adjusting section 50, FIG. 9 also shows the reading section 13, the signal processing section 15, and the storage section 16. FIG.

Although not shown in FIGS. 1 and 6, a data receiving and rearranging section 18 is normally provided in the preceding stage of the signal processing section 15. FIG. The data receiving and rearranging unit 18 receives analog-to-digital converted pixel data sequentially output from the signal processing unit 15, and divides the pixel data into a pixel block 100R, a pixel block 100Gr, a pixel block 100Gb, and a pixel block. A process of rearranging the pixels into a pixel array corresponding to the 100B RGB Bayer array is performed.

The signal amount adjustment unit 50 has a color-by-color digital gain correction processing unit 51. Under the correction processing by the color-by-color digital gain correction processing unit 51, the signal is acquired in advance at the stage before shipment and stored in the storage unit 16. Correction processing for absorbing the difference in the output signal amount for each color is performed based on the information on the output signal amount for each color. Specifically, the color-by-color digital gain correction processing unit 51 causes the data reception and rearrangement unit 18 to match the signal amounts of the pixels of a predetermined color after the rearrangement process with the output signal amounts of the respective colors. By adjusting the obtained gain, gain adjustment is performed to absorb the difference in output signal amount for each color. Here, "matching" means not only strictly matching but also substantially matching, and various variations caused by design or manufacturing are allowed.

The color-specific digital gain correction processing for absorbing the difference in the output signal amount for each color will be described in more detail below.

(For all pixel readout mode/AF mode)
As shown in a in FIG. 10, there is an all-pixel readout mode for individually reading the signals of the pixels 20 of the pixel block 100 (100R, 100Gr, Gb, 100B), and two pixels 20 forming a pixel pair 90. In the AF mode in which signals are added and read out, the output signal amount of R and B is larger than the output signal amount of G (Gr, Gb). The reason why there is a difference in the output signal amount for each color is that the conversion efficiency of the charge-voltage converter 23 is different for each color, as described above. Information about the difference in output signal amount is acquired in advance and stored in the storage unit 16 .

In the case of this all-pixel readout mode/AF mode, the color-by-color digital gain correction processing unit 51 of the signal amount adjustment unit 50, for example, at the initial stage of startup of the imaging device 1, outputs the output stored in the storage unit 16. Based on the information of the signal amount difference, as shown in b in FIG. The output signal amount is adjusted by digital gain correction so that the signal amount is increased and matched. That is, in this digital gain correction, correction is performed by multiplying the difference in conversion efficiency by the gain of the output signal amount of G(Gr, Gb).

The adjustment of the output signal amount by this color-by-color digital gain correction process absorbs the difference between the output signal amount of R, B and the output signal amount of G (Gr, Gb) in the case of all pixel readout mode and AF mode. , both can be matched. As a result, an output signal amount proportional to the exposure time can be obtained for each pixel 20 of the pixel block 100 (100R, 100Gr, Gb, 100B), so that a more legible photographed image can be obtained.

(For all pixel addition mode)
As shown by a in FIG. 11, in the case of the all-pixel addition mode in which the signals of all the pixels 20 of the pixel block 100 (100R, 100Gr, Gb, 100B) are added and read out, the output signal of G (Gr, Gb) is is greater than the R and B output signal amounts. The reason why the output signal amount of each color differs in this way is mainly because the number of electrons handled by the charge-voltage converter 23 increases due to the addition of all pixels. Information about the difference in output signal amount is acquired in advance and stored in the storage unit 16 .

In the case of this all-pixel addition mode, the color-by-color digital gain correction processing unit 51 of the signal amount adjustment unit 50 adjusts the output signal amount stored in the storage unit 16 at the initial stage of startup of the imaging device 1, for example. Based on the difference information, as shown in b in FIG. The output signal amount is adjusted by digital gain correction so that the output signal amount is increased and matched. That is, in this digital gain correction, a correction is performed by multiplying the R and B output signal amounts by a predetermined gain by the difference between the conversion efficiency and the number of pixels to be added.

By adjusting the output signal amount by this color-by-color digital gain correction process, the difference between the output signal amount of R and B and the output signal amount of G (Gr, Gb) in the case of all pixel addition mode is absorbed, and both are can be matched. As a result, an output signal amount proportional to the exposure time can be obtained for each pixel 20 of the pixel block 100 (100R, 100Gr, Gb, 100B), so that a more legible photographed image can be obtained.

<2. Second Embodiment>
FIG. 12 is a circuit diagram showing a configuration example of an analog-digital conversion unit according to the second embodiment of the present technology; The second embodiment is an example in which analog gain correction is performed to absorb the difference in output signal amount for each color. Note that the overall configuration of the imaging device 1 is the same as that of the above-described first embodiment, so detailed description thereof will be omitted.

In the first embodiment described above, the signal of each pixel 20 of the pixel block 100 (100R, 100Gr, Gb, 100B) is subjected to analog-to-digital conversion by the single-slope analog-to-digital converter 31. A single reference signal generator 14 for generating a reference signal RAMP used as a reference signal is provided for each color. That is, in the first embodiment, the slope of the reference signal RAMP is common to the pixel signals of each color, and the digital gain correction process for each color is performed in the digital domain after the analog-to-digital conversion by the analog-to-digital converter 31. It is configured to do

On the other hand, in the second embodiment, a plurality of reference signal generators 14, in this example, two reference signal generators 14A for R/B and a reference signal generator 14B for Gr/Gb. It has a configuration in which a signal generator is provided. The R/B reference signal generation unit 14A determines the output signal amount for each color of R/B output from the pixel block 100R and the pixel block 100B by analog gain determined by the slope of the generated ramp wave reference signal RAMP. A reference signal generator for adjustment. The Gr/Gb reference signal generation unit 14B calculates the output signal amount for each color of Gr/Gb output from the pixel block 100Gr and the pixel block 100Gb, using an analog gain determined by the slope of the generated ramp wave reference signal RAMP. A reference signal generator for adjustment.

In addition to the signal amount adjusting section 50 and the storage section 16, FIG. 12 also shows a DC generating section 19A for R/B and a DC generating section 19B for Gr/Gb. The R/B DC generator 19A generates a DC (Direct Current) voltage to be applied to the ramp wave reference signal RAMP output from the R/B reference signal generator 14A. The Gr/Gb DC generator 19B generates a DC voltage to be applied to the ramp wave reference signal RAMP output from the Gr/Gb reference signal generator 14B.

The signal amount adjustment unit 50 has a color-by-color digital gain correction processing unit 51. Under the correction processing by the color-by-color digital gain correction processing unit 51, the signal is acquired in advance at the stage before shipment and stored in the storage unit 16. Correction processing for absorbing the difference in the output signal amount for each color is performed based on the information on the output signal amount for each color. Specifically, the color-by-color digital gain correction processing unit 51 adjusts the slope of the ramp wave reference signal RAMP generated by each of the R/B reference signal generation unit 14A and the Gr/Gb reference signal generation unit 14B. By controlling the analog gain determined by the gain adjustment that absorbs the difference in the amount of output signal for each color.

FIG. 13 shows timing relationships among the waveform of the reference signal RAMP at high gain (RAMP waveform), the waveform of the reference signal RAMP at low gain, the waveform of the signal line VSL (VSL waveform), and the clock of the counter 314 (counter clock). is a waveform diagram showing . In the waveform diagram of FIG. 13, when the gain is low, the slope of the RAMP waveform becomes steep (that is, the voltage level of 1LSB increases) as indicated by the solid line. The slope of the waveform becomes gentler (that is, the voltage level of 1LSB becomes smaller). Also, when the gain is low, the count of the counter 314 is relatively small, and when the gain is high, the count of the counter 314 is relatively large. hanging).

The concept of the color-by-color digital gain correction processing for absorbing the difference in the output signal amount by color performed by the color-by-color digital gain correction processing unit 51 of the signal amount adjustment unit 50 is basically the same as that of the first embodiment. is the same as for the form of

(For all pixel readout mode/AF mode)
As indicated by a in FIG. 10, in the all pixel readout mode and the AF mode, the output signal amounts of R and B are larger than the output signal amount of G (Gr, Gb). In this case, the color-by-color digital gain correction processing unit 51 of the signal amount adjustment unit 50, for example, in the initial stage of startup of the imaging device 1, based on the information of the difference in the output signal amount stored in the storage unit 16. A low gain is set for the relatively large R and B output signal amounts, and a high gain is set for the relatively small G (Gr, Gb) output signal amount.

The low gain and high gain set here are determined by the slope of the ramp wave reference signal RAMP generated by the R/B reference signal generation unit 13A and the Gr/Gb reference signal generation unit 13B, respectively. is the gain. By this gain adjustment, as shown in b in FIG. 10, the output signal amount of G (Gr, Gb), which is relatively small, is increased with respect to the output signal amount of R, B, which is relatively large. That way you can match the two. As a result, an output signal amount proportional to the exposure time can be obtained for each pixel 20 of the pixel block 100 (100R, 100Gr, Gb, 100B), so that a more legible photographed image can be obtained.

(For all pixel addition mode)
As shown by a in FIG. 11, in the case of the all-pixel addition mode in which the signals of all the pixels 20 of the pixel block 100 (100R, 100Gr, Gb, 100B) are added and read out, the output signal of G (Gr, Gb) is is greater than the R and B output signal amounts. In this case, the color-specific digital gain correction processing unit 51 of the signal amount adjustment unit 50, based on the information on the difference in the output signal amount stored in the storage unit 16, at the initial stage of startup of the imaging device 1, A low gain is set for the relatively large G (Gr, Gb) output signal amount, and a high gain is set for the relatively small R and B output signal amounts.

By this gain adjustment, as shown in b in FIG. 11, the output signal amount of R and B, which are relatively small, is increased with respect to the output signal amount of G (Gr, Gb), which is relatively large. That way you can match the two. As a result, an output signal amount proportional to the exposure time can be obtained for each pixel 20 of the pixel block 100 (100R, 100Gr, Gb, 100B), so that a more legible photographed image can be obtained.

<3. Variation>
In addition, the above-described embodiment shows an example for embodying the present technology, and the matters in the embodiment and the matters specifying the invention in the scope of claims have corresponding relationships. Similarly, the matters specifying the invention in the scope of claims and the matters in the embodiments of the present technology with the same names have corresponding relationships. However, the present technology is not limited to the embodiments, and can be embodied by various modifications to the embodiments without departing from the scope of the present technology.

<4. Examples of application to electronic devices>
The image pickup device according to the embodiments of the present technology described above includes image pickup devices such as digital still cameras and video cameras, mobile terminal devices having an image pickup function such as mobile phones, and copying devices using an image pickup device as an image reading unit. It can be applied to various electronic devices having an imaging function such as a camera.

(Example of imaging device)
FIG. 14 is a block diagram showing a configuration example of an imaging device, which is an example of electronic equipment to which the present technology is applied.

An imaging device 200 according to this application example is a device for imaging a subject, and includes an imaging optical system 201 including a lens group and the like, an imaging unit 202, a DSP (Digital Signal Processor) circuit 203, a display unit 204, and an operation unit 205. , a storage unit 206 and a power supply unit 207 . These are interconnected by bus wiring 208 . As the imaging element 200, for example, in addition to a digital camera such as a digital still camera, a smart phone, a personal computer, an in-vehicle camera, and the like having an imaging function are assumed.

The imaging unit 202 generates pixel data by photoelectric conversion. As the imaging unit 202, the imaging device according to the above-described embodiment is used. In the imaging unit 202, the light from the subject is condensed by the imaging optical system 201 arranged on the incident light side and guided to its light receiving surface. The imaging unit 202 supplies pixel data generated by photoelectric conversion to the downstream DSP circuit 203 .

The DSP circuit 203 executes predetermined signal processing on the pixel data from the imaging unit 202 . The display unit 204 displays pixel data. As the display unit 204, for example, a liquid crystal panel or an organic EL (Electro Luminescence) panel is assumed. The operation unit 205 generates an operation signal according to a user's operation. The storage unit 206 stores various data such as pixel data. The power supply unit 207 supplies power to the imaging unit 202, the DSP circuit 203, the display unit 204, and the like.

<5. Application Example of Embodiment of Present Technology>
Embodiments of the present technology described above can be applied to various technologies as exemplified below.

FIG. 15 is a diagram showing an example of a field to which an embodiment of the present technology is applied.

The imaging device according to the embodiment of the present technology can be used as a device that captures an image for viewing, such as a digital camera or a mobile device with a camera function.

In addition, this imaging device includes an in-vehicle sensor that captures images of the surroundings and interior of a vehicle for safe driving such as automatic stopping and recognition of the driver's state, a surveillance camera that monitors running vehicles and roads, and an image sensor between vehicles. It can be used as a device for transportation, such as a ranging sensor that measures the distance of a vehicle.

In addition, this imaging device can be used as a device for home appliances such as televisions, refrigerators, air conditioners, etc., in order to capture a user's gesture and operate the device according to the gesture.

In addition, this imaging device can be used as a device for medical or healthcare purposes, such as an endoscope or an angiographic device that performs angiography by receiving infrared light.

In addition, this imaging device can be used as a security device such as a monitoring camera for crime prevention and a camera for personal authentication.

In addition, this imaging device can be used as a device used for beauty, such as a skin measuring instrument for photographing the skin and a microscope for photographing the scalp.

Also, this imaging device can be used as a device for sports, such as an action camera or wearable camera for sports.

In addition, this imaging device can be used as an agricultural device such as a camera for monitoring the state of fields and crops.

<6. Example of application to a moving object>
The technology (the present technology) according to the present disclosure can be applied to various products. For example, the technology according to the present disclosure can be realized as a device mounted on any type of moving body such as automobiles, electric vehicles, hybrid electric vehicles, motorcycles, bicycles, personal mobility, airplanes, drones, ships, and robots. may

FIG. 16 is a block diagram showing a schematic configuration example of a vehicle control system, which is an example of a mobile control system to which the technology according to the present disclosure can be applied.

A vehicle control system 12000 includes a plurality of electronic control units connected via a communication network 12001. In the example shown in FIG. 16, the vehicle control system 12000 includes a drive train control unit 12010, a body system control unit 12020, an outside information detection unit 12030, an inside information detection unit 12040, and an integrated control unit 12050. Also, as the functional configuration of the integrated control unit 12050, a microcomputer 12051, an audio/image output unit 12052, and an in-vehicle network I/F (interface) 12053 are illustrated.

The drive system control unit 12010 controls the operation of devices related to the drive system of the vehicle according to various programs. For example, the driving system control unit 12010 includes a driving force generator for generating driving force of the vehicle such as an internal combustion engine or a driving motor, a driving force transmission mechanism for transmitting the driving force to the wheels, and a steering angle of the vehicle. It functions as a control device such as a steering mechanism to adjust and a brake device to generate braking force of the vehicle.

The body system control unit 12020 controls the operation of various devices equipped on the vehicle body according to various programs. For example, the body system control unit 12020 functions as a keyless entry system, a smart key system, a power window device, or a control device for various lamps such as headlamps, back lamps, brake lamps, winkers or fog lamps. In this case, body system control unit 12020 can receive radio waves transmitted from a portable device that substitutes for a key or signals from various switches. The body system control unit 12020 receives the input of these radio waves or signals and controls the door lock device, power window device, lamps, etc. of the vehicle.

The vehicle exterior information detection unit 12030 detects information outside the vehicle in which the vehicle control system 12000 is installed. For example, the vehicle exterior information detection unit 12030 is connected with an imaging section 12031 . The vehicle exterior information detection unit 12030 causes the imaging unit 12031 to capture an image of the exterior of the vehicle, and receives the captured image. The vehicle exterior information detection unit 12030 may perform object detection processing or distance detection processing such as people, vehicles, obstacles, signs, or characters on the road surface based on the received image.

The imaging unit 12031 is an optical sensor that receives light and outputs an electrical signal according to the amount of received light. The imaging unit 12031 can output the electric signal as an image, and can also output it as distance measurement information. Also, the light received by the imaging unit 12031 may be visible light or non-visible light such as infrared rays.

The in-vehicle information detection unit 12040 detects in-vehicle information. The in-vehicle information detection unit 12040 is connected to, for example, a driver state detection section 12041 that detects the state of the driver. The driver state detection unit 12041 includes, for example, a camera that captures an image of the driver, and the in-vehicle information detection unit 12040 detects the degree of fatigue or concentration of the driver based on the detection information input from the driver state detection unit 12041. It may be calculated, or it may be determined whether the driver is dozing off.

The microcomputer 12051 calculates control target values for the driving force generator, the steering mechanism, or the braking device based on the information inside and outside the vehicle acquired by the vehicle exterior information detection unit 12030 or the vehicle interior information detection unit 12040, and controls the drive system control unit. A control command can be output to 12010 . For example, the microcomputer 12051 realizes the functions of ADAS (Advanced Driver Assistance System) including collision avoidance or shock mitigation, follow-up driving based on inter-vehicle distance, vehicle speed maintenance driving, vehicle collision warning, or vehicle lane deviation warning. Cooperative control can be performed for the purpose of

In addition, the microcomputer 12051 controls the driving force generator, the steering mechanism, the braking device, etc. based on the information about the vehicle surroundings acquired by the vehicle exterior information detection unit 12030 or the vehicle interior information detection unit 12040, so that the driver's Cooperative control can be performed for the purpose of autonomous driving, etc., in which vehicles autonomously travel without depending on operation.

Also, the microcomputer 12051 can output a control command to the body system control unit 12020 based on the information outside the vehicle acquired by the information detection unit 12030 outside the vehicle. For example, the microcomputer 12051 controls the headlamps according to the position of the preceding vehicle or the oncoming vehicle detected by the vehicle exterior information detection unit 12030, and performs cooperative control aimed at anti-glare such as switching from high beam to low beam. It can be carried out.

The audio/image output unit 12052 transmits at least one of audio and/or image output signals to an output device capable of visually or audibly notifying the passengers of the vehicle or the outside of the vehicle. In the example of FIG. 16, an audio speaker 12061, a display unit 12062, and an instrument panel 12063 are illustrated as output devices. The display unit 12062 may include at least one of an on-board display and a head-up display, for example.

FIG. 17 is a diagram showing an example of the installation position of the imaging unit 12031. FIG.

In FIG. 17, the imaging unit 12031 has

imaging units

12101, 12102, 12103, 12104, and 12105.

The

imaging units

12101, 12102, 12103, 12104, and 12105 are provided at positions such as the front nose of the vehicle 12100, the side mirrors, the rear bumper, the back door, and the upper part of the windshield in the vehicle interior, for example. An image pickup unit 12101 provided in the front nose and an image pickup unit 12105 provided above the windshield in the passenger compartment mainly acquire images in front of the vehicle 12100 .

Imaging units

12102 and 12103 provided in the side mirrors mainly acquire side images of the vehicle 12100 . An imaging unit 12104 provided in the rear bumper or back door mainly acquires an image behind the vehicle 12100 . The imaging unit 12105 provided above the windshield in the passenger compartment is mainly used for detecting preceding vehicles, pedestrians, obstacles, traffic lights, traffic signs, lanes, and the like.

Note that FIG. 17 shows an example of the imaging range of the imaging units 12101 to 12104. FIG. The imaging range 12111 indicates the imaging range of the imaging unit 12101 provided in the front nose, the imaging ranges 12112 and 12113 indicate the imaging ranges of the

imaging units

12102 and 12103 provided in the side mirrors, respectively, and the imaging range 12114 The imaging range of an imaging unit 12104 provided in the rear bumper or back door is shown. For example, by superimposing the image data captured by the imaging units 12101 to 12104, a bird's-eye view image of the vehicle 12100 viewed from above can be obtained.

At least one of the imaging units 12101 to 12104 may have a function of acquiring distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera composed of a plurality of imaging elements, or may be an imaging element having pixels for phase difference detection.

For example, based on the distance information obtained from the imaging units 12101 to 12104, the microcomputer 12051 determines the distance to each three-dimensional object within the imaging ranges 12111 to 12114 and changes in this distance over time (relative velocity with respect to the vehicle 12100). , it is possible to extract, as the preceding vehicle, the closest three-dimensional object on the course of the vehicle 12100, which runs at a predetermined speed (for example, 0 km/h or more) in substantially the same direction as the vehicle 12100. can. Furthermore, the microcomputer 12051 can set the inter-vehicle distance to be secured in advance in front of the preceding vehicle, and perform automatic brake control (including following stop control) and automatic acceleration control (including following start control). In this way, cooperative control can be performed for the purpose of automatic driving in which the vehicle runs autonomously without relying on the operation of the driver.

For example, based on the distance information obtained from the imaging units 12101 to 12104, the microcomputer 12051 converts three-dimensional object data related to three-dimensional objects to other three-dimensional objects such as motorcycles, ordinary vehicles, large vehicles, pedestrians, and utility poles. It can be classified and extracted and used for automatic avoidance of obstacles. For example, the microcomputer 12051 distinguishes obstacles around the vehicle 12100 into those that are visible to the driver of the vehicle 12100 and those that are difficult to see. Then, the microcomputer 12051 judges the collision risk indicating the degree of danger of collision with each obstacle, and when the collision risk is equal to or higher than the set value and there is a possibility of collision, an audio speaker 12061 and a display unit 12062 are displayed. By outputting an alarm to the driver via the drive system control unit 12010 and performing forced deceleration and avoidance steering via the drive system control unit 12010, driving support for collision avoidance can be performed.

At least one of the imaging units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 can recognize a pedestrian by determining whether or not the pedestrian exists in the captured images of the imaging units 12101 to 12104 . Such recognition of a pedestrian is performed by, for example, a procedure for extracting feature points in images captured by the imaging units 12101 to 12104 as infrared cameras, and performing pattern matching processing on a series of feature points indicating the outline of an object to determine whether or not the pedestrian is a pedestrian. This is done by a procedure that determines When the microcomputer 12051 determines that a pedestrian exists in the images captured by the imaging units 12101 to 12104 and recognizes the pedestrian, the audio image output unit 12052 outputs a rectangular outline for emphasis to the recognized pedestrian. is superimposed on the display unit 12062 . Also, the audio/image output unit 12052 may control the display unit 12062 to display an icon or the like indicating a pedestrian at a desired position.

An example of a vehicle control system to which the technology according to the present disclosure can be applied has been described above. The technology according to the present disclosure can be applied to, for example, the imaging unit 12031 among the configurations described above. Specifically, the imaging device 1 in FIG. 1 can be applied to the imaging unit 12031 . By applying the technology according to the present disclosure to the imaging unit 12031, it is possible to obtain an output signal amount proportional to the exposure time, and to obtain a more viewable photographed image, thereby reducing driver fatigue. Become.

It should be noted that the above-described embodiment shows an example for embodying the present technology, and the matters in the embodiment and the matters specifying the invention in the scope of claims have corresponding relationships. Similarly, the matters specifying the invention in the scope of claims and the matters in the embodiments of the present technology with the same names have corresponding relationships. However, the present technology is not limited to the embodiments, and can be embodied by various modifications to the embodiments without departing from the scope of the present technology.

It should be noted that the effects described in this specification are only examples and are not limited, and other effects may also occur.

<7. Configuration that this technology can take>
Note that the present technology can also have the following configuration.
(1) a first pixel block having a plurality of pixels each including color filters of a first color that are the same as each other;
a second pixel block each having a plurality of pixels including a color filter of a second color that is the same as that of the first pixel block and different from that of the first pixel block; a pixel block;
each of the first pixel block and the second pixel block has a plurality of pixel pairs of two pixels;
A plurality of lenses are provided at respective positions corresponding to the plurality of pixel pairs,
The first pixel block and the second pixel block have a pixel-sharing configuration in which a plurality of pixels share pixel constituent elements after the charge-voltage conversion unit that converts the charge obtained by the photoelectric conversion unit into voltage. and
further comprising a signal amount adjustment unit that adjusts an output signal amount output from each pixel of the first pixel block and the second pixel block;
The signal amount adjustment unit adjusts the output signal amount for the first color output from the first pixel block and the output signal amount for the second color output from the second pixel block. image sensor that adjusts the amount of output signal so that
(2) The signal amount adjustment unit adjusts the output signal amount for the first color output from the first pixel block and the output signal amount for the second color output from the second pixel block. The output signal amount is adjusted so that the output signal amount of the color with the smaller signal amount matches the output signal amount of the color with the larger signal amount with respect to the output signal amount. image sensor.
(3) The signal amount adjusting section is configured to set a first drive mode for individually reading signals of pixels of the first pixel block and the second pixel block, and signals of the two pixels of the pixel pair. in the second driving mode in which the second driving mode is read out by adding the second The imaging device according to (2) above, wherein the output signal amount is adjusted so that the output signal amount for each color is matched.
(4) The signal amount adjustment section outputs signals from the second pixel block in a third driving mode for adding and reading signals of all pixels of the first pixel block and the second pixel block. The (2 ).
(5) The signal amount adjustment unit performs the adjustment of the output signal amount in the digital domain after converting the analog signal output from each pixel of the first pixel block and the second pixel block into a digital signal. The imaging device according to (1) above, which is performed by digital gain adjustment in .
(6) The signal amount adjustment unit adjusts the output signal amount for each color before converting the analog signal output from each pixel of the first pixel block and the second pixel block into a digital signal. The imaging device according to (1) above, which is performed by analog gain adjustment in an analog domain.
(7) The analog-to-digital conversion unit, which converts analog signals to digital signals, uses a ramp wave reference signal whose level changes with a predetermined slope as time elapses as a reference signal for analog-to-digital conversion. A slope-type analog-to-digital converter,
The imaging device according to (6), wherein the signal amount adjustment unit performs analog gain adjustment by changing a slope of the reference signal of the ramp wave.
(8) the two pixels are arranged side by side in a first direction;
In each of the first pixel block and the second pixel block, the two pixel pairs aligned in a second direction crossing the first direction are arranged with a shift in the first direction. The imaging device according to (1) above.
(9) a first pixel block having a plurality of pixels each including color filters of the same first color;
a second pixel block each having a plurality of pixels including a color filter of a second color that is the same as that of the first pixel block and different from that of the first pixel block; a pixel block;
an analog-to-digital converter that converts an analog signal output from each pixel of the first pixel block and the second pixel block into a digital signal;
each of the first pixel block and the second pixel block has a plurality of pixel pairs of two pixels;
A plurality of lenses are provided at respective positions corresponding to the plurality of pixel pairs,
The first pixel block and the second pixel block have a pixel-sharing configuration in which a plurality of pixels share pixel constituent elements after the charge-voltage conversion unit that converts the charge obtained by the photoelectric conversion unit into voltage. and
The analog-digital conversion unit is a single-slope analog-digital conversion unit that uses the reference signal of the ramp wave provided from the reference signal generation unit as a reference signal for analog-digital conversion,
A plurality of reference signal generators for generating reference signals of ramp waves having different slopes are provided as the reference signal generators,
further comprising a signal amount adjustment unit that adjusts an output signal amount output from each pixel of the first pixel block and the second pixel block;
The signal amount adjustment unit adjusts the first color output from the first pixel block based on the ramp wave reference signals with different slopes generated by the plurality of reference signal generation units. An imaging device that adjusts an output signal amount so that the output signal amount and the output signal amount for the second color output from the second pixel block match.
(10) The plurality of reference signal generation units include a reference signal generation unit for adjusting an output signal amount for the first color output from the first pixel block, and the second pixel block. The imaging device according to (9) above, which is a reference signal generation unit for adjusting the output signal amount for the second color output from.
(11) a first pixel block having a plurality of pixels each including color filters of the same first color;
a second pixel block each having a plurality of pixels including a color filter of a second color that is the same as that of the first pixel block and different from that of the first pixel block; a pixel block;
each of the first pixel block and the second pixel block has a plurality of pixel pairs of two pixels;
A plurality of lenses are provided at respective positions corresponding to the plurality of pixel pairs,
The first pixel block and the second pixel block have a pixel-sharing configuration in which a plurality of pixels share pixel constituent elements after the charge-voltage conversion unit that converts the charge obtained by the photoelectric conversion unit into voltage. and
further comprising a signal amount adjustment unit that adjusts an output signal amount output from each pixel of the first pixel block and the second pixel block;
The signal amount adjustment unit adjusts the output signal amount for the first color output from the first pixel block and the output signal amount for the second color output from the second pixel block. An electronic device having an image pickup device that adjusts the output signal amount so that the

1 Imaging Device 11 Pixel Array Section 12 Driving Section 13 Reading Section 14 Reference Signal Generation Section 15 Signal Processing Section 16 Storage Section 17 Imaging Control Section 18 Data Receiving & Sorting Section 20 Pixel 21 Photoelectric Conversion Section (Photodiode)
22 transfer transistor 23 charge-voltage converter 24 reset transistor 25 amplification transistor 25
26

selection transistor

41, 43, 44 semiconductor substrate 50 signal amount adjustment unit 51 digital gain correction processing unit for each color 90 pixel pair 100 (100R, 100Gr, 100Gb, 100B) pixel block

Claims

a first pixel block having a plurality of pixels each including color filters of a first color that are the same as each other;
a second pixel block each having a plurality of pixels including a color filter of a second color that is the same as that of the first pixel block and different from that of the first pixel block; a pixel block;
each of the first pixel block and the second pixel block has a plurality of pixel pairs of two pixels;
A plurality of lenses are provided at respective positions corresponding to the plurality of pixel pairs,
The first pixel block and the second pixel block have a pixel-sharing configuration in which a plurality of pixels share pixel constituent elements after the charge-voltage conversion unit that converts the charge obtained by the photoelectric conversion unit into voltage. and
further comprising a signal amount adjustment unit that adjusts an output signal amount output from each pixel of the first pixel block and the second pixel block;
The signal amount adjustment unit adjusts the output signal amount for the first color output from the first pixel block and the output signal amount for the second color output from the second pixel block. image sensor that adjusts the amount of output signal so that
The signal amount adjustment unit adjusts the output signal amount of the first color output from the first pixel block and the output signal amount of the second color output from the second pixel block. 2. The image pickup device according to claim 1, wherein the output signal amount is adjusted so that the output signal amount of the color with the smaller signal amount matches the output signal amount of the color with the larger signal amount.
The signal amount adjustment unit is configured to perform a first drive mode in which signals of pixels of the first pixel block and the second pixel block are individually read out, and signals of the two pixels of the pixel pair are added. in the second drive mode in which the second color output from the second pixel block is 3. The imaging device according to claim 2, wherein the output signal amount is adjusted so as to match the output signal amount of each.
The signal amount adjusting section, in a third drive mode for adding and reading out signals of all pixels of the first pixel block and the second pixel block, outputs the second signal output from the second pixel block. 3. The method according to claim 2, wherein the output signal amount is adjusted so as to match the output signal amount for the first color output from the first pixel block with the output signal amount for the second color. image sensor.
The signal amount adjustment unit adjusts the output signal amount by digital gain in a digital domain after converting analog signals output from each pixel of the first pixel block and the second pixel block into digital signals. 2. The imaging device according to claim 1, wherein the adjustment is performed.
The signal amount adjustment unit adjusts the output signal amount for each color in an analog domain before converting the analog signal output from each pixel of the first pixel block and the second pixel block into a digital signal. 2. The imaging device according to claim 1, wherein the adjustment is performed by analog gain adjustment.
The analog-to-digital converter, which converts analog signals to digital signals, is a single-slope reference signal that uses a ramp wave reference signal whose level changes with the passage of time with a predetermined slope as a reference signal for analog-to-digital conversion. an analog-to-digital converter,
7. The image pickup device according to claim 6, wherein the signal amount adjustment section performs analog gain adjustment by changing a slope of the reference signal of the ramp wave.
the two pixels are arranged side by side in a first direction;
In each of the first pixel block and the second pixel block, the two pixel pairs aligned in a second direction crossing the first direction are arranged with a shift in the first direction. The imaging device according to claim 1 .
a first pixel block having a plurality of pixels each including color filters of a first color that are the same as each other;
a second pixel block each having a plurality of pixels including a color filter of a second color that is the same as that of the first pixel block and different from that of the first pixel block; a pixel block;
an analog-to-digital converter that converts an analog signal output from each pixel of the first pixel block and the second pixel block into a digital signal;
each of the first pixel block and the second pixel block has a plurality of pixel pairs of two pixels;
A plurality of lenses are provided at respective positions corresponding to the plurality of pixel pairs,
The first pixel block and the second pixel block have a pixel-sharing configuration in which a plurality of pixels share pixel constituent elements after the charge-voltage conversion unit that converts the charge obtained by the photoelectric conversion unit into voltage. and
The analog-digital conversion unit is a single-slope analog-digital conversion unit that uses a ramp wave reference signal provided from the reference signal generation unit as a reference signal for analog-digital conversion,
A plurality of reference signal generators for generating reference signals of ramp waves having different slopes are provided as the reference signal generators,
further comprising a signal amount adjustment unit that adjusts an output signal amount output from each pixel of the first pixel block and the second pixel block;
The signal amount adjustment unit adjusts the first color output from the first pixel block based on the ramp wave reference signals with different slopes generated by the plurality of reference signal generation units. An imaging device that adjusts an output signal amount so that the output signal amount and the output signal amount for the second color output from the second pixel block match.
The plurality of reference signal generation units include a reference signal generation unit for adjusting an output signal amount for the first color output from the first pixel block, and a reference signal generation unit for adjusting an output signal amount for the first color output from the first pixel block. 10. The image sensor according to claim 9, which is a reference signal generation unit for adjusting the output signal amount for the second color.
a first pixel block having a plurality of pixels each including color filters of a first color that are the same as each other;
a second pixel block each having a plurality of pixels including a color filter of a second color that is the same as that of the first pixel block and different from that of the first pixel block; a pixel block;
each of the first pixel block and the second pixel block has a plurality of pixel pairs of two pixels;
A plurality of lenses are provided at respective positions corresponding to the plurality of pixel pairs,
The first pixel block and the second pixel block have a pixel-sharing configuration in which a plurality of pixels share pixel constituent elements after the charge-voltage conversion unit that converts the charge obtained by the photoelectric conversion unit into voltage. and
further comprising a signal amount adjustment unit that adjusts an output signal amount output from each pixel of the first pixel block and the second pixel block;
The signal amount adjustment unit adjusts the output signal amount for the first color output from the first pixel block and the output signal amount for the second color output from the second pixel block. An electronic device having an image pickup device that adjusts the output signal amount so that the